The Orange County Register says the rejection came in a July 31 letter. However, Navy officials say they’ll continue working with the commission to resolve differences.

At issue is a Navy plan for sonar and underwater explosives training in Southern California and Hawaii between 2014 and 2019.

Conservationists fear the noise could do damage to marine mammals and lead to whale strandings.

In March, the coastal commission urged the Navy to stop training in some areas at times when certain marine mammals are known to be present — for instance, during August and September when blue whales are in California.